Untitled Quiz

Study Notes

Located in the dome of the diaphragm within the abdominal cavity
Has four main lobes (left, quadrate, right, and caudate)
In some animal species, the left and right lobes have medial and lateral sections
The caudate lobe has caudate and papillary processes
The liver's position allows for movement due to diaphragm
The gall bladder is present in some animals (carnivores, ruminants, pigs, mice) but not in others (horses, rats). Bile is still produced but not stored in these species.

A fibrous capsule surrounds the liver, extending into the liver tissue forming branched septa
These septa demarcate functional units called hepatic lobules
Hepatocytes are the primary functional liver cells; they absorb molecules from the space of Disse through the sinusoidal membrane.
Bile canaliculi are the spaces between hepatocytes where bile is secreted, and are part of a network leading to larger bile ducts

Bile travels from the liver to the duodenum
Bile is secreted across hepatocyte membranes into canaliculi then small bile ducts
These ducts anastomose into larger ducts that coalesce to form hepatic bile ducts
The bile duct enters the duodenum via the sphincter of Oddi
Bile moves between the gall bladder and bile duct via the cystic duct

The hepatic portal vein supplies 75% of the liver's blood
The hepatic artery supplies the remaining 25%
Blood from both sources mixes in sinusoids (venous and arterial blood)
Sinusoids empty into central veins
Central veins combine to form hepatic veins, which drain into the caudal vena cava

Carbohydrate metabolism (glycogenesis, glycogenolysis, gluconeogenesis)
Lipid metabolism (fatty acid oxidation, ketone bodies, cholesterol, phospholipids, bile acid synthesis)
Protein metabolism (deamination, transamination of amino acids, synthesis of non-essential amino acids)

Shaped like hexagons
Consists of hepatocytes radiating out from a central vein
Portal triads (bile duct, hepatic artery, hepatic portal vein) are located between lobules

Purifies, transforms, and clears substances from the gastrointestinal tract (entering via hepatic portal vein)
Converts harmful substances into less harmful ones
Hepatocyte microsomes contain enzymes that oxidize substances (cytochrome P450) for further degradation or conjugation to make them water-soluble for excretion

Red blood cells (RBCs) are broken down by macrophages in the spleen and liver
Hemoglobin is broken down to yield heme and globin
Heme is converted to biliverdin, then to bilirubin
Bilirubin is transported to the liver, conjugated, and excreted into bile
Bilirubin in the gut is metabolised by bacteria to stercobilin which gives feces its colour.